mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-10-31 14:15:30 +00:00
85 lines
2.5 KiB
C++
85 lines
2.5 KiB
C++
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
|
|
/*
|
|
* The contents of this file are subject to the Netscape Public License
|
|
* Version 1.0 (the "License"); you may not use this file except in
|
|
* compliance with the License. You may obtain a copy of the License at
|
|
* http://www.mozilla.org/NPL/
|
|
*
|
|
* Software distributed under the License is distributed on an "AS IS" basis,
|
|
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
|
|
* for the specific language governing rights and limitations under the
|
|
* License.
|
|
*
|
|
* The Original Code is Mozilla Communicator client code,
|
|
* released March 31, 1998.
|
|
*
|
|
* The Initial Developer of the Original Code is Netscape Communications
|
|
* Corporation. Portions created by Netscape are
|
|
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
|
|
* Reserved.
|
|
*
|
|
* Contributors:
|
|
*/
|
|
|
|
/* A set of support classes for defining weak references, rather like
|
|
nsIWeakReference, but for use with non-COM objects
|
|
*/
|
|
|
|
#include "nsCWeakReference.h"
|
|
|
|
/************ a thing supporting weak references to itself ***********/
|
|
nsCWeakReferent::nsCWeakReferent(void *aRealThing) :
|
|
mRealThing(aRealThing),
|
|
mProxy(0) {
|
|
|
|
}
|
|
|
|
nsCWeakReferent::~nsCWeakReferent() {
|
|
|
|
if (mProxy)
|
|
mProxy->RealThingDeleted();
|
|
}
|
|
|
|
void nsCWeakReferent::SetReferent(void *aRealThing) {
|
|
|
|
NS_ASSERTION(!mRealThing && !mProxy, "weak referent set twice");
|
|
mRealThing = aRealThing;
|
|
mProxy = 0;
|
|
}
|
|
|
|
nsCWeakProxy *nsCWeakReferent::GetProxy() {
|
|
|
|
if (!mProxy)
|
|
mProxy = new nsCWeakProxy(mRealThing, this);
|
|
return mProxy;
|
|
}
|
|
|
|
/************ a reference proxy whose lifetime we control ***********/
|
|
/* the nsCWeakProxy object is an object whose creation and lifetime is
|
|
under our control, unlike the nsCWeakReferent and its family of
|
|
nsCWeakReferences. An nsCWeakProxy is created by the nsCWeakReferent
|
|
when the first weak reference is necessary, and refcounted for each
|
|
additional reference. It knows about the lifetime of the nsCWeakReferent,
|
|
and deletes itself once all weak references have been broken.
|
|
*/
|
|
nsCWeakProxy::nsCWeakProxy(void *aRealThing, nsCWeakReferent *aReferent) :
|
|
mRealPointer(aRealThing),
|
|
mReferent(aReferent),
|
|
mRefCount(0) {
|
|
|
|
NS_ASSERTION(aRealThing && aReferent, "weak proxy constructed with null ptr");
|
|
}
|
|
|
|
nsCWeakProxy::~nsCWeakProxy() {
|
|
if (mReferent)
|
|
mReferent->ProxyDeleted();
|
|
}
|
|
|
|
void nsCWeakProxy::ReleaseReference() {
|
|
|
|
if (--mRefCount == 0) {
|
|
delete this;
|
|
}
|
|
}
|
|
|